In the food industry, filling processes are often controlled during filling based on the filling amount of a container. For example, the filling of a container can be terminated when a predetermined filling amount is reached. One possibility of determining the filling amount during filling is the use of a weighing means which determines the mass of the container to be filled by means of strain gauges and calculates the filling amount from it.
For this, the strain gauges, which change their electric resistance in case of deformations, are adhered to a component with a special adhesive, the component minimally deforming under load during the filling process. This deformation (extension) then leads to a change of the resistance of the strain gauge from which in turn the mass or the weight of the container to be filled can be calculated. Such filling devices are described in, for example, EP 1 025 424 or DE 10 2008 030 721.
However, it is a disadvantage of such filling devices that the service life of the strain gauges is restricted to a predetermined number of measuring cycles, usually to about 10 million measuring cycles. Using the strain gauges beyond this point can result in material fatigue and thus falsified measuring results, which in turn can result in inaccurate filling amounts.